Vertically moving cantilever platform



Nov. 19, 1968 R. H. M KAY VERTICALLY MOVING CANTILEVER PLATFORM 3Sheets-Sheet 1 Filed June 16, 1966 I NVENTOR. Robert H. MacKay 3Sheets-Sheet Nov. 19, 1968 R. H. M KAY VERTICALLY MOVING CANTILEVERPLATFORM Filed June 16. 1966 INVENTOR. Robert H. MacKay BY M M ATTORNE SR. H. M KAY Nov. 19, 1968 VERTICALLY MOVING CANTILEVER PLATFORM 3Sheets-Sheet 5 Filed June 16, 1966 a WEE?" INVENTOR. Robert H. MacKayATTORNEYS United States Patent 3,411,464 VERTICALLY MOVING CANTILEVERPLATFORM Robert H. MacKay, Fort Wayne, Ind., assignor to LincolnManufacturing Company, Fort Wayne, Ind., a corporation of Indiana FiledJune 16, 1966, Ser. No. 558,020 7 Claims. (Cl. 108-136) ABSTRACT OF THEDISCLOSURE A vertically movable platform is supported by flexible cableswound about a roller that is positioned at a fixed location above theplatform. The roller is spring loaded so that dishes on the platformremain at a fixed level.

My invention relates to a vertically moving cantilever platform, andparticularly to such a platform for dining apparatus or utinsels.

Dining apparatus or utensils, such as trays or racks of glasses, arefrequently stacked vertically to make the most efiicient utilization ofavailable floor space. Previously, users of such stacked apparatus orutensils had to take a piece of the apparatus or a utensil from thestack at whatever height the next available piece happened to be. Thenext available piece might be inconveniently high or low. In addition,used pieces of apparatus or used utensils had to be stacked elsewhere orat some distance from the stack of clean apparatus or utensils. Suchadditional stacking required additional floor space.

Accordingly, an object of my invention is to provide an improved,vertically moving platform for supporting dining apparatus or utensils,the platform moving upward as pieces of apparatus or as utensils areremoved so that the top utensil or piece of apparatus remains atsubstantially the same predetermined height.

Another object of my invention is to provide an improved platform thatsupports a stack of din-ing apparatus or equipment, and that movesvertically upward as such apparatus or equipment is removed to provideadditional storage space beneath the platform for used apparatus orequipment.

Another object of my invention is to provide an improved, vertically'moving platform that comprises a spring for actuating the platformupwardly, the spring being tensioned by the apparatus or equipmentplaced on the platform, and the spring raising the platform as pieces ofapparatus or equipment are removed.

Prior art devices for stacking dining apparatus or equipment wereaccessible only from the top. In addition, cleaning of these prior artdevices was difiicult. These devices were inconvenient in that thestacked apparatus or equipment was not freely accessible. Also, thesedevices did not utilize the available space to the best advantage. Andfinally, these prior are devices were relatively ditficult to clean.

Accordingly, another object of my invention is to provide an improved,vertically moving cantilever platform on which dining apparatus orequipment can be stacked in a more accessible manner.

Another object of my invention is to provide an improved verticallymoving platform that is relatively easy to clean and that is for use indining establishments or kitchens.

Another object of my invention is to provide a platform verticallyactuated by a sealed spring assembly, the platform being for diningapparatus or equipment and being easily cleaned or sterilized with hotliquids and strong cleansers without special protection or disassembly.

Briefly, these and other objects are achieved in accordance with myinvention by a structure comprising a base which may be either movableor stationary. First and second vertical guides are fastened to the baseand extend upward in parallel directions from the base. A rolling ormoving bearing structure is mounted on each of the guides and arrangedso as to slide up and down its respective guide with substantially notransverse or canting. A horizontally extending arm is fastened to eachguide, and a platform is fastened to both arms to support the diningapparatus or equipment. The platform causes the arms and the bearingstructures to move as a unit. A roller mechanism is rotatably mounted onthe base or the vertical guides, preferably at the top of the verticalguides. This roller mechanism contains a torsion spring which istensioned or wound to cause the roller mechanism to rotate in onedirection. The roller mechanism includes one or more flexible cablesfastened at one end and wound about the roller. The other end isconnected to the unit comprising the platform, the arms, and the bearingstructures. The platform tends to maintain the top of the diningapparatus or utensils stacked on the platform at a given height.

The subject matter which I regard as my invention is particularlypointed out and distinctly claimed in the claims. The structure andoperation of my invention, together with further objects and advantages,may be better understood from the following description given inconnection with the accompanying drawing, in which:

FIGURE 1 shows a side elevation view, partly in cross section, of acantilever platform in accordance with my invention;

FIGURE 2 shows a plan view of the cantilever platform of FIGURE 1;

FIGURE 3 shows a cross sectional view taken along the lines 33 of FIGURE1;

FIGURE 4 shows a view, partly in cross section, of the spring and rollermechanism for the platform;

FIGURE 5 shows an end view of the spring and roller mechanism of FIGURE4; and

FIGURES 6 and 7 show elevation and cross sectional views respectively ofa modification of the cantilever platform in accordance with myinvention.

The cantilever platform shown in the various figures has been assumed tobe used for trays or racks of glasses. However, it is to be understoodthat the platform may be shaped or designed to hold any particular typeof dining apparatus or utensils. As shown in FIGURE 1, the platform inaccordance with my invention comprises a horizontal base 10 which may bestationary, or which may be mounted on wheels or rollers 11 'as shown. Apair of vertical guides 13, 14 are attached to the base 10 at spacedlocations, and extend vertically upward in parallel directions. InFIGURE 1, only one vertical guide 13 is visible, but FIGURE 2 shows thelocation of both vertical guides 13, 14. Each of the vertical guides 13,14 is supported by or fastened to respective sides 15, 16 by horizontalsupport brackets 17, 18. The structure may be provided with a suitableback 19 (with a handle), a front 20 (with suitable slits or openings),and a top 21 which provide additional strength and also seal thestructure to some extent. The structure as thus far described may beassembled in any convenient fashion, as by welding or riveting.

The two vertical guides (FIGURE 3 shows the vertical guide 13) aresubstantially identical, and each comprises an intermediate sectionwhich is formed or bent so that it has a channel or groove 24 at one endof the intermediate section, and a channel or groove 25 at the other endof the intermediate section. These channels 24, 25 face each other andserve as tracks or guides for a set of four rollers 27, 28, 29, 30 whichare fastened to respective and similar support arms 31, 32. The supportarm 31 runs up and down on its respective rollers in the channels of thevertical support 13, and the support arm 32 runs up and down on itsrespective rollers in the channels of the vertical support 14. Thus, thetwo support arms 31, 32 are supported for vertical movement in or bytheir respective vertical supports 13, 14. The support arms 31, 32 arepreferably symmetrical, and extend outward in the direction from thestructure, as shown in FIGURE 1. A suitable platform 33 is attached tothe two support arms 31, 32 so that the support arms 31, 32 and theplatform 33 move as a unit. With respect to FIGURE 1, it will be notedthat the support arms 31, 32 and the platform 33 are supported incantilever fashion. Actually only the two rollers 27, are needed toprovide this cantilever support. However, it has been found that the twoadded rollers 28, 29 provide further guidance and tend to eliminatebinding or reduce friction.

As shown in FIGURES 1 and 2, the unit comprising the support arms 31, 32and the platform 33, is supported by a pair of flexible wires or cables35, 36 which are respectively attached to the support arms 31, 32. Thesewires or cables extend upward from the support arms 31, 32 and aresimilarly wound a number of times around respective sleeves 39, 40 andthen securely attached to these sleeves by screws or other fasteningelements. The sleeves 39, 40 are supported on a roller tube 42. Theroller tube 42 is mounted, as will be described, for rotation insuitable tube brackets 43, 44 which are respectively fastened to thesides 15, 16.

FIGURE 4 shows details of the construction of the roller tube 42 and itsinternal elements. The sleeves 39, 40 are securely fastened to androtate with the roller tube 42. The rollerv tube 42 is a hollow,cylindrical metallic structure which is supported at its two ends byball bearing structures 45, 46. These ball bearing structures 45, 46 aresupported on a shaft 48 so that the roller tube 42 is free to rotatewith respect to the shaft 48. A helical spring 49, preferably wound ofrectangular Wire, is positioned around and extends for substantially thefull length of the shaft 48. The left end of the spring 49 is mountedfor rotation with the roller tube 42 by a spring roller hub 52. Thisspring roller hub 52 is positioned inside and is fastened to the leftend of the roller tube 42 by any suitable means such as the machinescrew shown in FIGURE 4. The spring roller hub 52 has an internal boreor hole which permits this hub 52 to rotate freely on the shaft 48. Theleft end 50 of the spring 49 is attached to the hub 52 by any suitablemeans, such as by a force or press fit which, in connection with thepitch or direction of rotation of the spring 49, causes the end 50 ofthe spring 49 to grip the spring roller hub 52 more tightly as thespring 49 is tensioned. The right end 51 of the spring 49 is fastened tothe shaft 48 by a spring shaft hub 53. This hub 53 is securely fastenedto the shaft 48, and the right end 51 of the spring is attached to thehub 53 in any suitable manner, such as by the force or press fitprovided at its left end 50. Thus the structure shown in FIGURE 4supports the roller tube 42 for rotation relative to the shaft 48. Asthe roller tube 42 rotates, it rotates the left end 50 of the spring 49.The right end 51 of the spring 49 is fastened securely to the shaft 48.The shaft 48 is, in turn, secured against rotation by a shaped or keyedend 55 which, as shown in FIGURE 5, has flat, parallel edges which fitinto a correspondingly shaped groove or notch 56 in the tube bracket 44,as shown in FIGURE 2. The other end of the shaft 48 is inserted in ahole in the tube bracket 43, and supported thereby.

With the cables 35, 36 wrapped in the proper direction around theirrespective sleeves 39, 40, as the platform 33 is moved downward, thiscauses the roller tube 42 to rotate. As the roller tube 42 rotates, ittransmits this rotational motion through the spring roller hub 52 to theleft end 50 of the spring 49 so as to wind or tension the spring 49 moretightly. It will be recalled that the right end 51 of the spring 49 istilted to the shaft 48, and the shaft 48 is prevented from rotating byits keyed end 55. Thus, downward motion of the platform 33 causes thesprin 49 to wind up more tightly or to have more tension. Conversely, asthe platform 33 moves upward, the tension in the spring 49 is reduced.Or, expressed in another manner, if the weight on the platform 33 isreduced, the tension in the spring 49 turns the roller tube 42 to windthe cables and move the platform 33 upward. It will thus be seen thatthe structure provides means which permit the platform 33 to movedownward when weight is applied or added thereto. This downward movementplaces increased tension on the spring 49 until the tension on thespring 49 and the added weight reach a point of equilibrium. As weightis removed from the platform 33, the tension on the spring 49 causes theplatform 33 to move upward until the tension on the spring 49 and thereduced weight reach a new point of equilibrium. Because of therelatively long length of the spring 49, it has been found that itsforce is linear over a substantially wide range of applied forces ortensions. Thus, if the platform 33 is adjusted for a predetermined stackof dining apparatus such as trays, the removal of each tray from thestack will permit the spring 49 to provide a slight upward motion of theplatform 33 so that the topmost tray on the stack remains atsubstantially the same height. The tension on the spring 49 may beadjusted by removing the keyed or shaped end 55 of the shaft 48 from itsnotch 56; turning the shaft 48 in either direction by a wrench orsimilar tool to provide the desired tension; holding the shaft positionby the wrench or tool; and inserting the keyed or shaped end 55 of theshaft 48 back into its notch 56. FIGURE 1 shows an upper position of theplatform and support arms in phantom lines.

FIGURES 6 and 7 show another embodiment of my invention, FIGURE 7 beingtaken along the lines 77 in FIGURE 6. In this embodiment, the verticalguides 13, 14 shown in the previous figures have been replaced by a pairof vertical tubes 60 which serve as supports for two support arms 61.The support arms 61 are mounted for movement along the vertical tubes 60by sleeve or roller bearings 62 which fit around the outside of thevertical tubes 60 as shown in FIGURE 7. It is preferable that upper andlower sleeve bearings 62 be provided in order to provide propercantilever support. Also an additional sleeve hearing may be provided ifdesired. The other structure for the tray platform is otherwise the sameas that shown in FIGURES 1 through 5.

It will thus be seen that my invention provides a new and improved,vertically moving, cantilever supported platform. This platform isaccessible from a plurality of directions, and can be easily cleaned.The main moving or motivating element, namely the torsion spring, may besealed within the roller tube so as to protect it against water andcleansers. The relatively long length of this spring provides arelatively wide range of weight or forces which can be accommodated onthe platform. Persons skilled in the art will appreciate thatmodifications may be made to my invention. For example, other cantileversupport structures may be provided. The roller tube may have only onesleeve with a cable for moving the platform, or the roller tube may beprovided with more sleeves and cables for moving the platform. And, theroller tube may be positioned at other locations (such as on the base)if the cables can be threaded through pulleys to the proper locations.The roller tube may also be positioned on the vertical guides.Therefore, while my invention has been described with reference to aparticular embodiment, it is to be understood that modifications may bemade without departing from the spirit of my invention or from the scopeof the claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. A platform for movement up and down, comprising:

(a) a base;

(b) first and second vertical guides fastened to said base, said guidesbeing spaced from each other and extending vertically upward from saidbase;

(c) first bearing means mounted on said first guide and arranged toslide up and down on said first guide; (d) second bearing means mountedon said second guide and arranged to slide up and down on said secondguide;

(e) horizontal platform means fastened to said first and second bearingmeans, said first and second bearing means and said horizontal platformmeans being movable as a unit up and down along said first and secondguides;

(f) a roller mechanism rotatably mounted in a fixed location withrespect to said first and second guides, said roller mechanism havingrotational biasing means associated therewith that tend to rotate saidroller mechanism in a predetermined direction;

(g) and flexible means connected at one end to said roller mechanism andextending vertically downward therefrom, the other end of said flexiblemeans being connected to said unit of said horizontal platform means andsaid bearing means for moving said unit upward in response to the forceof said biasing means exceeding the weight on said platform, and formoving said unit downward in response to the force on said unit thatexceeds the forcing of said rotational biasing means.

2. A cantilever platform for dining apparatus and utensils or the like,comprising:

(a) a base;

(b) first and second elongated support elements each having one endfastened to said base, said support elements each extending verticallyupward in the same parallel direction from said base;

(c) first and second movable elements positioned on said first andsecond support elements respectively for movement along said supportelements in substantially only a direction parallel thereto;

(d) a platform fastened to and supported in cantilever fashion by saidfirst and second movable elements for keeping said first and secondmovable elements at substantially the same distance from said base andfor moving with said first and second movable elements as a unit;

(e) a rotatable element mounted at a fixed location on said supportelements near the top thereof;

(f) Spring bias means having one end fixed and the other end connectedto said rotatable element;

(g) and means comprising at least one fiexible member having one endwrapped around and attached to said rotatable element, extendingvertically downward from said rotatable element, and having the otherend attached to said unit for increasing the tension on said spring biasmeans in response to increased downward force applied to said unit, andfor causing said unit to move upward in response to decreased downwardforce applied to said unit.

3. The cantilever platform of claim 2 wherein said spring bias meanscomprises a helical spring wound about a shaft, said spring and shaftbeing positioned Within said rotatable element.

4. The cantilever platform of claim 3 wherein said one end of saidhelical spring is fastened to one end of said shaft, and said other endof said helical spring is fastened to said rotatable element at the endthereof away from said one end of said shaft.

5. The cantilever platform of claim 2 wherein said first and secondsupport elements each comprise a pair of spaced vertical channels facingeach other, and wherein said first and second movable elements eachcomprise a set of rollers respectively mounted in said channels topermit vertical motion of said movable elements and to support said unitin cantilever fashion.

6. The cantilever platform of claim 2 wherein said first and secondsupport elements each comprise a tubular structure, and wherein saidfirst and second movable elements each comprise an elongated sleevebearing positioned around said tubular structure to permit verticalmotion of said movable elements and the support said unit in cantileverfashion.

7. The cantilever platform of claim 3 and further comprising first andsecond sleeves mounted on said rotatable elements, and first and secondcables wrapped around and attached to said sleeve at one end andattached to said unit at the other end.

References Cited UNITED STATES PATENTS 1,359,399 11/1920 Lewis 108-1473,123,023 3/1964 Bronson 108-136 3,123,024 3/1964 Bronson 1081363,123,829 3/1964 Bronson 108136 3,154,029 10/1964 Bronson 108-436 JAMEST. MCCALL, Primary Examiner.

